d- and f-Block Elements PYQs Set 14 (PDF)

Set 14 of 15 · Questions 391-420 of 443

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Mere Teacher · Previous Year Questions JEE Main Chemistry · d- and f-Block Elements · Set 14 (Q391-420)
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391. $When sulphur dioxide is passed in an acidified K_{2} Cr_{2} O_{7} solution, the oxidation state of sulphur is changed from$ (1) $+4 to +6$ (2) $+6 to +4$ (3) $+4 to 0$ (4) $+4 to +2$ 392. $The catalytic activity of transition metals and their compounds is ascribed mainly to$ (1) $their magnetic behaviour$ (2) $their unfilled d ‐orbitals$ (3) $their ability to adopt variable oxidation states$ (4) $their chemical reactivity$ 393. $Silver iodide is used for producing artificial rain because AgI$ (1) $is easy to spray at high altitude$ (2) $is easy to synthesize$ (3) $has crystal structure similar to ice$ (4) $is insoluble in water.$ 394. $Which of the following has the maximum number of unpaired d electrons?$ (1) $Ni^{3 +}$ (2) $Cu^{+}$ (3) $Zn^{2 +}$ (4) $Fe^{2 +}$ 395. $MSO_{4} \to NH_{4} OH X ↓ \to NH_{4} OH Excess white Y \to H_{2} S ZL Here M and Z are$ (1) $Zn, ZnS$ (2) $Al, Al_{2} S_{3}$ (3) $Cu, ZnS$ (4) $Fe, FeS$ 396. $The only radioactive element among the lanthanoids is$ (1) $gadolinium$ (2) $holmium$ (3) $promethium$ (4) $neodymium.$ 397. $Aqueous solution of a salt (A) forms a dense white precipitate with BaCl_{2} solution. The precipitate dissolves in dilute HCl to produce a gas (B) which decolourises acidified KMnO_{4} solution. A and B respectively are$ (1) $BaSO_{4}, H_{2} S$ (2) $BaSO_{4}, SO_{2}$ (3) $BaSO_{3}, H_{2} S$ (4) $BaSO_{3}, SO_{2}$ 398. $The number of element from the following that do not belong to lanthanoids is Eu, Cm, Er, Tb, Yb and Lu$ (1) $3$ (2) $4$ (3) $1$ (4) $5$ 399. $Which one of the following exhibits the largest number of oxidation states?$ (1) $Ti (22)$ (2) $V(23)$ (3) $Cr (24)$ (4) $Mn (25)$ 400. $Which of the following element is responsible for oxidation of water to O_{2} in biological processes?$ (1) $Cu$ (2) $Mo$ (3) $Fe$ (4) $Mn$ 401. $Magnetic moment 2.83 BM is given by which of the following ions? (At.nos.Ti=22,Cr=24, Mn=25, Ni=28)$ (1) $Ti3+$ (2) $Ni2+$ (3) $Cr3+$ (4) $Mn2+$ 402. $The transition metal ions responsible for color in ruby and emerald are, respectively$ (1) $C r^{3 +} and C r^{3 +}$ (2) $C o^{3 +} and C o^{3 +}$ (3) $C o^{3 +} and C r^{3 +}$ (4) $C r^{3 +} and C o^{3 +}$ 403. $The electronic configuration of_{59} Pr (praseodimium) is$ (1) $(_{54} Xe) 4 f^{2} 5 d^{1} 6 s^{2}$ (2) $(_{54} Xe) 4 f^{1} 5 d^{1} 6 s^{2}$ (3) $(_{54} Xe) 4 f^{3} 6 s^{2}$ (4) $(_{54} Xe) 4 f^{3} 5 d^{2}$ 404. $The transition element that has lowest enthalpy of atomisation, is:$ (1) $V$ (2) $Fe$ (3) $Zn$ (4) $Cu$ 405. $The electronic configuration of Gd^{2 +} is (at. no. of Gd is 64)$ (1) $[Xe] 4 f^{7}$ (2) $[Xe] 4 f^{7} 5 d^{I}$ (3) $[Xe] 4 f^{8}$ (4) $[Xe] 4 f^{7} 5 d^{1} 6 s^{2}$ 406. $Which of the following exhibit only + 3 oxidation state ?$ (1) $U$ (2) $Th$ (3) $Ac$ (4) $Pa$ 407. $Identify the element for which electronic configuration in +3 oxidation state is [A r]^{3} d^{5} :$ (1) $Ru$ (2) $Mn$ (3) $Co$ (4) $Fe$ 408. $The elements in which electrons are progressively filled in 4 f orbital are called$ (1) $actinoids$ (2) $transition elements$ (3) $lanthanoids$ (4) $halogens.$ 409. $The correct order of decreasing second ionization enthalpy of Ti (22), V (23), Cr (24) and Mn (25) is :$ (1) $Cr > Mn > V > Ti$ (2) $V > Mn > Cr > Ti$ (3) $Mn > Cr > Ti > V$ (4) $Ti > V > Cr > M$ 410. $The percentage of lanthanides and iron, respectively, in misch metal are$ (1) $50,50$ (2) $75,25$ (3) $90,10$ (4) $95,5$ 411. $Chloro compound of Vanadium has only spin magnetic moment of 1.73 BM. This Vanadium chloride has the formula : (at. no. of V = 23)$ (1) $V C l_{2}$ (2) $V C l_{4}$ (3) $V C l_{3}$ (4) $V C l_{5}$ 412. $Which of the following configuration is correct for iron$ (1) $1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{2} 3 d^{7}$ (2) $1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{2} 3 d^{5}$ (3) $1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{5}$ (4) $1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{2} 3 d^{6}$ 413. $Which of the following forms a colourless solution in aqueous medium?$ (1) $Cr^{3 +}$ (2) $V^{3 +}$ (3) $Sc^{3 +}$ (4) $Ti^{3 +}$ 414. $Gadolinium belongs to 4 f series. Its atomic number is 64. Which of the following is the correct electronic configuration of gadolinium7$ (1) $[X e] 4 f^{9} 5 s^{1}$ (2) $[X e] 4 f^{7} 5 d^{1} 6 s^{2}$ (3) $[X e] 4 f^{6} 5 d^{2} 6 s^{2}$ (4) $[X e] 4 f^{8} 6 d^{2}$ 415. $Copper becomes green when exposed to moist air for a long period. This is due to :$ (1) $the formation of a layer of cupric oxide on the surface of copper.$ (2) $the formation of a layer of basic carbonate of copper on the surface of copper.$ (3) $the formation of a layer of cupric hydroxide on the surface of copper.$ (4) $the formation of basic copper sulphate layer on the surface of the metal.$ 416. $Which of the following oxidation states is common for all lanthanides?$ (1) $+2$ (2) $+3$ (3) $+4$ (4) $+5$ 417. $Match the catalyst with the process: Catalyst Process (i) V_{2} O_{5} (p) The oxidation of ethyne to ethanal (ii) T i C l_{4} + A l (C H_{3})_{3} (q) Polymerisation of alkynes (iii) P d C l_{2} (r) Oxidation of S O_{2} in the manufacture of H_{2} S O_{4} (iv) Nickel complexes (s) Polymerisation of ethylene Which of the following is the correct option?.$ (1) $(i) - (r), (ii) - (s), (iii) - (p), (i v) - (q)$ (2) $(i) - (p), (ii) - (q), (iii) - (r), (i v) - (s)$ (3) $(i) - (p), (ii) - (r), (iii) - (q), (i v) - (s)$ (4) $(i) - (r), (ii) - (p), (iii) - (s), (i v) - (q)$ 418. $A white crystalline salt A reacts with dilute HCl to liberate a suffocating gas B and also forms a yellow precipitate. The gas B turns potassium dichromate acidified with dilute H_{2} SO_{4} to a green coloured solution C, A, B and C are respectively$ (1) $Na_{2} SO_{3}, SO_{2}, Cr_{2} (SO_{4})_{3}$ (2) $Na_{2} S_{2} O_{3}, SO_{2}, Cr_{2} (SO_{4})_{3}$ (3) $Na_{2} S, SO_{2}, Cr_{2} (SO_{4})_{3}$ (4) $Na_{2} SO_{4}, SO_{2}, Cr_{2} (SO_{4})_{3}$ 419. $Which of the following statements is wrong?$ (1) $In highest oxidation states, the transition metals show acidic character.$ (2) $Mn^{3 +} and Co^{3 +} are oxidising agents in aqueous solution.$ (3) $Metals in highest oxidation states are more stable in oxides than in fluorides.$ (4) $All elements of 3 d series exhibit variable oxidation states.$ 420. $a MnO_{4}^{-} + b S_{2} O_{3}^{2 -} + H_{2} O \to x MnO_{2} + y SO_{4}^{2 -} + z OH^{-} a and y respectively are$ (1) $8; 3$ (2) $8; 6$ (3) $3; 6$ (4) $8; 8$